An interesting argument... Roar or Haze. I'd say Haze is more beneficial in battle, especially if your opponent has pokemon who beef up their stats, or drains your own stats. Though Roar also has a multitude of uses, but it's more of a risk, unless you're double battling. I guess it all really depends on the situation of the battle you're in.
Adventure Started(Diamond): April 22, 2007(11:38 a.m. U.S. Release)
Seen: 493, Owned: 493
Legit: Mewtwo, Ho-oh, Lugia, Deoxys, Jirachi, Darkrai, Shaymin.
Non-Legit: Mew(working on Ranch), Celebi, Arceus.
Platinum will be untainted.